Tire-mold.



w.A. ROBBINS.

TIRE MOLD.

APPLICATION FILED APR- 26. 1913.

1,156,180. Patented 001.12, 1915.

I 2 SHEETSSHEET I.

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W. A. ROBBINS.

TIRE MOLD.

APPLICATION FILED APR-26,1913.

Patented Oct. 12, 1915.

2 SHEETSSHEET 2.

- [nveniwv ll 11am 5506.5 @715 sear WILLIAM A. Remains, or GLEN RIDGE, NEW JERSEY.

TIRE-MOLD.

Specification of Letters Patent. Patented Oct. 1 2, 1915.

Application filed April 26, 1913 Serial N 0. 763,699.

To all whom it may concern:

Be it known that I, WILLIAM A. ROBBINS,

a citizen of the United States, residing in Glen Ridge, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Tire- Molds, of which the following is aspecification. The object of my invention is to provide molds in which pneumatic tires can be accurately, safely, and symmetrically. formed, and with a perfect interior surface for contact with the pneumatic tube, and in whose normal use it will be impossible for the members of such tire to become upset, overlapped, unsymmetrlcally disposed, or unequally strained.

In the use of entirely rigid models it frequently occurs that the fabric members hecome unsymmetrical in some of the plies of fabrics in the wall at various places, and the wall is upset in these places and unequally strained; and therefore the tires have weak zones or zones of unequal elasticity, and are therefore short lived, misshapen, and unsatisfactory in use. In other known methods of manufacture, these unsymmetrical spots, or wrinkles, cause rough inner surfaces which chafe or wear out the inner tube, as well as weakening the walls of the shoe.

My invention remedies these defects by proriding, in a metal, multiple part mold, a highly finished core or forming member which properly forms and locates the tire in the mold: a forming chamber considerably longer than, and practically concentric with, the tire; an impervious flexible formative or pressure-transmitting diaphragm whose edges make water-tight joints with the mold bodies and which divides the forming chamber into a tire chamber and a hydraulic chamber, respectively, interior and exterior to said diaphragm; and a source of hydraulic power suitably connected with said hydraulic ch mber, and valve-controlled.

Inthe drawings, Figure 1 is a partial axial view or plan of. my improved mold,

and Figs. 2, 3 and 4 are cross-sections through a limb, respectively illustrating three variants of my invention.

In the practice of my invention I form a mold, 1, of two similar and matching cylindrical. metal copes, 2, provided with lugs 3, by which they can bolted up; two similar "and matching interior metal cheeks, 4, and a highly-finished metal core or forming'means, 5, located in the transverse central plane of the mold. The shank 5 of the core 5 engages corresponding re-' cesses in the cheeks l, and shoulders 4: on the cheeks engage corresponding recesses in the-copes 2; and thus the mold members are accurately centered and alined. In the faces of the cheeks I turn bead-grooves 4 conforming with the contour of the tirebeads. The faces of the copes 2 are turned out substantially concentric with, and somewhat longer than, thetire, so that when assembled the mold-members inclose a forming chamber 6, whose interior wall is the face of the core 5 and whose exterior walls are the faces of the copes 2 and cheeks 4.

v ()n the adjacent faces of the cope checks, 1 form seats 7, and I provide a flexible, yet

sensibly stiff, or rather nearly rigid forma- 'tive diaphragm 8, whose heel flanges 8 are clamped between and make tight joints 7 with the seats 7 whose interior contour when chamber 6 into an interior tire chamber 9 anda hydraulic chamber 10; and I connect the latter by pipes 11 with a source of hydraulic power.

In the simplest variant, illustrated in Fig. 4, the diaphragm 8 joins the mold only at the seats 7, and the hydraulic chamber 19 is unital; and I make a tight circumferential ioint between'the copes 2, by means of a suitable packing 22. In the use of this;

variant the mold isassembled inclosing an assembled, but as yet unsolidified and untreated, tire in the tire chamber 9. Water under pressure i then admitted tothe hydraulicchamber 10, presses the formative. diaphragm 8 against-the tire and the reaction of the core 5, and solidifies it without danger .of upsetting or unequally. straining its well orcausing unsymmetrical distribution ofthe reinforcing strip, fabric wall and tread-stock. In this variantthere is a pos 'sibility that the reinforcing strip and tread may be flattened and thinned at the crown;

cent thereto.

As illustrated in Fig. 2, I inter-pose between the copes, outer cheek-rings, 53.; form the diaphragm in two halves 88; make tight joints between their crown-flanges 8" and the -cop es and outer cheeks; divide the hydraulic chamber into two parts, 10; and connect each, by a pipe or branch 11, with a source of hydraulic power.

In the variant illustrated in Fig. 3, I form the diaphragm of halves, united at the crown by a lapped ointand with outturned cup-flanges 8 adapted to make cup-joints with the outer cheeks. Either of these variants is used in the manner heretofore set forth. In that illustrated in Fig. 2 there will be slight tins formed around the joints between the diaphragm halves 8S and the outer cheeks 55, which will not occur in the variant illustrated in Fig. 3.

I may provide screws, 20, as shown in dotted lines, to secure the cheeks in the copes; but such are notnecessarv. I may form patterns m, or m, upon the formative surface of the diaphragm 8 corresponding with any characters or surface configurations which it may be desired to impress upon the exposed surface of the tire, such as numbers, legends, ribs, or lozenge forms.

It is obvious from all of the foregoing that other fluid pressure means can be used besides hydraulic pressure.

Having thus described my invention, I claim:

1. The combination in a fluid pressure tire mold comprising two rigid outer members and two rigid inner members, a rigid core positioned centrally interior to said outer members and clamped in place between said two inner members, and two flexible water- 't1ght formative diaphragm members form-.

ing a tire receiving chamber, said diaphragm members being clamped at their outer abutting free annular edges between the abutting edges of the outer members at the tread portion of the tire being treated, and at their inner free annular edges between theouter and innermembers at the clencher portions of the tire beingtreated.

2. The combination in a fluid pressure tire mold comprising rigid and removable centrally interior to said enveloping mom-- bers, outer cheek rings between said enveloping members, and a flexible water tight formative diaphragm making tight joints with said enveloping members adjacent to its heel and crown. said. cheek rings forming contour limiting means fo rthe tread portion of aid tire.

t. The eoml'iination in a fluid pressure tire mold comprising two rigid outer envelop members and two rigid inner enveloping mei'nbers, a rigid core positioned cent-rally interior to said outer enveloping members and clamped in place between said two inner enveloping members, said enveloping members inclosing a forming chamber, and two flexible water-tight formative diaphragm. members dividing said forming chamber into a pressure transmitting chamber and tire receiving chamber, said diaphragm members being clamped at their outer abut ting free annular edges between the abutting edges of the outer enveloping members at the tread portion of the tire being treat ed, and at their inner tree annular edges between the outer and inner enveloping members at the clencher portions of the tire be ing treated.

a. The combination in a fluid pressure tire mold comprising "two rigid outer annular members and two rigid inner annular members, arigid core positioned centrally interior to said outer annular members and clamped in place between said inner annular members, and a flexible water-tight format tive diaphragm forming a tire receiving chamber, said diaphragm clamped at its inner tree annular edges between the outer and inner annular members at the clencher portions of the tire being treated.

. WILLIAM A. ROBBINS.

Witnesses:

FRED. J. DOLE, HAROLD D. PENNEY. 

